A simulation is made of the propagation of a thermo-optical traveling wave along a silicon wafer surface containing an isolated optical inhomogeneity which critically changes a balance of input and output heat in the position of the localization of the wave. The optical inhomogeneity is represented by a strip of sputter-coated material with high reflectivity which is applied on the wafer and whose reflectivity and width are varied in the simulation process. Depending on these parameters, the traveling wave either delays its propagation passing through the optical inhomogeneity or stops at a boundary of the strip. It has been shown that a critical width of the strip at which a thermooptical traveling wave is localized increases as strip reflectivity decreases.